Theorem eqvrelsymb 38562

Description: An equivalence relation is symmetric. (Contributed by NM, 30-Jul-1995.) (Revised by Mario Carneiro, 12-Aug-2015.) (Revised and distinct variable conditions removed by Peter Mazsa, 2-Jun-2019.)

Hypothesis

Ref	Expression
eqvrelsymb.1	⊢ (𝜑 → EqvRel 𝑅)

Assertion

Ref	Expression
eqvrelsymb	⊢ (𝜑 → (𝐴𝑅𝐵 ↔ 𝐵𝑅𝐴))

Proof of Theorem eqvrelsymb

Step	Hyp	Ref	Expression
1		eqvrelsymb.1	. . . 4 ⊢ (𝜑 → EqvRel 𝑅)
2	1	adantr 480	. . 3 ⊢ ((𝜑 ∧ 𝐴𝑅𝐵) → EqvRel 𝑅)
3		simpr 484	. . 3 ⊢ ((𝜑 ∧ 𝐴𝑅𝐵) → 𝐴𝑅𝐵)
4	2, 3	eqvrelsym 38561	. 2 ⊢ ((𝜑 ∧ 𝐴𝑅𝐵) → 𝐵𝑅𝐴)
5	1	adantr 480	. . 3 ⊢ ((𝜑 ∧ 𝐵𝑅𝐴) → EqvRel 𝑅)
6		simpr 484	. . 3 ⊢ ((𝜑 ∧ 𝐵𝑅𝐴) → 𝐵𝑅𝐴)
7	5, 6	eqvrelsym 38561	. 2 ⊢ ((𝜑 ∧ 𝐵𝑅𝐴) → 𝐴𝑅𝐵)
8	4, 7	impbida 800	1 ⊢ (𝜑 → (𝐴𝑅𝐵 ↔ 𝐵𝑅𝐴))

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   class class class wbr 5166   EqvRel weqvrel 38152

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1793  ax-4 1807  ax-5 1909  ax-6 1967  ax-7 2007  ax-8 2110  ax-9 2118  ax-ext 2711  ax-sep 5317  ax-nul 5324  ax-pr 5447

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 847  df-3an 1089  df-tru 1540  df-fal 1550  df-ex 1778  df-sb 2065  df-clab 2718  df-cleq 2732  df-clel 2819  df-ral 3068  df-rex 3077  df-rab 3444  df-v 3490  df-dif 3979  df-un 3981  df-in 3983  df-ss 3993  df-nul 4353  df-if 4549  df-sn 4649  df-pr 4651  df-op 4655  df-br 5167  df-opab 5229  df-id 5593  df-xp 5706  df-rel 5707  df-cnv 5708  df-co 5709  df-dm 5710  df-rn 5711  df-res 5712  df-refrel 38468  df-symrel 38500  df-trrel 38530  df-eqvrel 38541

This theorem is referenced by:  eqvrelth  38567